Research and analysis

HAIRS risk assessment: squirrel Bornavirus

Qualitative assessment of the risk that variegated squirrel Bornavirus presents to the UK population.


HAIRS risk assessment: novel squirrel Bornavirus

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Three fatal cases of encephalitis were reported in 2015 which had occurred between 2011 and 2013 in Germany and were associated with a novel Bornavirus species. A further human case, also a fatal encephalitis, due to the same novel Bornvirus was reported in 2018. This risk assessment was carried out to determine the level of risk to the UK population.

Published 8 September 2016
Last updated 12 September 2018 + show all updates
  1. Updated risk assessment.
  2. Updated risk assessment following detection of the virus in a second subfamily of squirrels.
  3. First published.